const fs = require('fs');
const path = require('path');

const BANNER_FILE = path.join(__dirname, '../../data/banner.json');

function readBanner() {
  try {
    const raw = fs.readFileSync(BANNER_FILE, 'utf8');
    return JSON.parse(raw);
  } catch {
    return { message: '', type: 'info', liveFrom: null, liveTill: null };
  }
}

function writeBanner(data) {
  fs.writeFileSync(BANNER_FILE, JSON.stringify(data, null, 2), 'utf8');
}

// @desc  Get the current banner
// @route GET /api/banner
// @access Public
const getBanner = (req, res) => {
  res.json(readBanner());
};

// @desc  Set the banner
// @route POST /api/banner
// @access Supervisor / Admin
const setBanner = (req, res) => {
  const { message, type, liveFrom, liveTill } = req.body;

  const allowed = ['info', 'warning', 'success', 'danger'];
  const banner = {
    message: typeof message === 'string' ? message.trim() : '',
    type: allowed.includes(type) ? type : 'info',
    liveFrom: liveFrom || null,
    liveTill: liveTill || null,
  };

  writeBanner(banner);
  res.json(banner);
};

module.exports = { getBanner, setBanner };